The bomber crossed the road and walked towards the Naval Complex, but then stopped and sat along a footpath.

The officer said sketches of the suicide bomber had been prepared, adding that samples taken from his severed limbs had been sent for DNA tests.

Meanwhile, investigators are also trying to trace a suspect, who was caught studying the area around the entrance last month but released on bail, sources said.

The Naval Police (NP) had detained AG, a resident of Sargodha, on November 18 when he was spotted acting suspiciously at Zafar Chowk, the site of the Wednesday bombing.

He was given into the custody of the Naval Intelligence personnel, who recovered a digital camera and an identification card issued by a Western country in his name. The card with identification number 20424 is to expire on November 23, 2010.

The motorcycle he was using also carried fake registration plates, as the number (IDM-5250) was originally issued for a car.

Investigation also revealed that he was on some kind of reconnaissance mission around the naval and air headquarters.

On the complaint of a navy official, Ansar Abbas, the suspect was handed over to the Margalla police for ‘the surveillance and reconnaissance of restricted military area, photographing sensitive installations and using motorcycle with fake registration.’

A case was registered and he was sent to Adiala Jail, but he was released on bail on November 20.